What is the Lombard effect?

Each of you has surely experienced the Lombard effect. This phenomenon refers to the increasing level of speech level if the speaker tries to talk in a noisy environment. This leads to the creation of additional noise and actually to an overall increase in noise in the room.

The effect was discovered in 1909 by Etienne Lombard, a French otolaryngologist. The Lombard effect is nothing new, it was already described more than 100 years ago, and we at Potich also try to mitigate the Lombard effect with professional noise reduction.

The Lombard effect suggests that if the noise level increases by 1 dB, the speech level increases by 0.5 dB. In a noisy environment, speakers, therefore, increase the volume or pitch of their speech. The more people in a room, the higher the general noise level, for example in restaurants or call centers.

In simple terms, the Lombard effect describes the effect of noise on speech production: when a speaker is exposed to noise, he increases the volume of his speech so that he can still be understood in a noisy environment. However, the responder will usually increase not only the volume, but in many cases, the tone of their voice, as high frequencies are more effective against background noise than low frequencies.

What causes the Lombard effect?

• Increasing the basic phonetic frequencies of the speaker,
• shift of energy from low-frequency bands to medium or high bands,
• increase in sound intensity,
• increase in vowel duration,
• the duration of content words is extended to a greater extent in noise than function words,
• larger lung volumes are used,
• it is accompanied by larger facial movements, although these do not help as much as sound changes.

In the absence of room acoustic measurements, these ever-increasing noise levels lead to fatigue and a lack of motivation. Therefore, soundproofing the premises is very important. Keep it professional and measure the noise level. We will advise you on how you can limit the unpleasant Lombard effect.